byte

A series of bits, usually eight in
number, used in computers to represent
a character. Byte is a contraction of the words "by eight." Half
a byte is sometimes called a "nibble." Originally, computers used
8-bit bytes but gradually this has increased to 16-, 32-, and 64-bit bytes.

A kilobyte is approximately one thousand bytes. Because
computers use a binary number system, a kilobyte is precisely 210
or 1,024 bytes.

A megabyte is approximately one million bits. It is precisely
220 bits, or 1,048,576 bits.

A gigabyte is approximately one billion bytes. It is precisely
230 or 1,073,741,824 bytes.

A terabyte is approximately one trillion bytes. It is precisely
240 or 1,099,511,627,776 bytes.